ASA5506 Spanning Tree Protocol problem

[petsoft.eu]

Hi

When I have boot system disk0:/asa961-lfbff-k8.SPA on ASA5506 and

setup:

access-list ERTHER ethertype deny bpdu

access-group ERTHER in interface outside

access-group ERTHER in interface inside

my ASA do not populate Spanning Tree Protocol to the router. Every thing work well.

After upgrade to:

boot system disk0:/asa981-lfbff-k8.SPA

Spanning Tree Protocol block router port under Spanning Tree attack.

Setup "ethertype deny bpdu" does not work any more.

Where is the problem ??

[Dennis Mink]

how did you configure the port on the router, connecting the asa?  as a trunk port running stp? if so the router will send bpdu's so the asa will shit the port.

if you have layer3 interfaces towards the router, then dont worry about spanning tree.